Disc cutter



United States Patent lnventor John D. Holley 339 Washington Ave., Montgomery, Ala.

Appl. No. 841,450

Filed July 14, 1969 Patented Dec. 29, 1970 DlSC CUTTER 11 Claims, 5 Drawing Figs.

US. Cl. 175/122, 125/20, 173/33, 173/37: 175/250, 175/403 Int. Cl E2lc 13/02 Field of Search 175/122,

as l

[56] References Cited UNITED STATES PATENTS 568,077 9/1896 Thonar 173/33X 2,084,686 6/ 1 937 Howard l25/20X 2,760,757 8/1956 Donaldson et a1. 173/37X 3,351,143 1l/1967 Seibold et a1. l73/32X 3,491,844 1/1970 Kelly 175/162X Primary Examiner-Ernest R. Purser Attorney-Cameron, Kerkam and Sutton ABSTRACT: A cutter for removing circular discs from paved surfaces includes a frame mounted on a wheeled support and legs supporting the frame when in position to cut a disc. A hollow cylindrical cutter having teeth on its lower periphery is lowered into engagement with the surface from which the disc is to be removed and is rotated by suitable driving motors. When the cutter has severed a disc, a vacuum grab engages and lifts the disc out of the opening.

PATENTED [18329 I970 sum 1 CF 4 INVENTOR M r JOHN D. HOLLEY PATENIED [ED291970 SHEET 2 OF 4 IN VENTOR JOHN D. HOLLEY ATTORNEYS PATENTEDDECZQISYU 3.550.701

sum 3 OF 4 FIG. 5.

JOHN D. HOLLEY %,Wm vM ATTORNEYS PATENTED UEC29 I970 SHEET t 0F 4 FIG. 5.

INVENTOR JOHN D. HOLLEY mam s w ATTORNIY'IYS P m BACKGROUND OF-Tl-IEINVENTION The present invention relates to disc cutters for cutting discs from paved surfaces such as streets and sidewalks when it is necessary to excavate beneath'suchsurfaces as in the repair, maintenanceor installationof pipelines, telephone conduits,

support. The drivinglmotor of the wheeled support may also drive a vacuum pump for creating a vacuum for a grab which engages the severed disc and lifts it out of the opening. The

present invention may be broadly classified under stone working, disc cutting; also under tool driving or impacting; and may preferably raised, lowered androtated by hydraulic means supplied by a pump driven by the drivingmotorof the wheeled A second hollow tubular member of square cross section (FIG. 3) is slidably mounted on member 18 and carries cutter frame head 26 on its lower end. Head 26 will be described in detail hereinaftenA third hollow tubular member 27 square in cross section is slidably mounted on member 25 and carries vacuum head 28 on its lower end. Vacuumhe'ad 28 will be described in more detail hereinafter. Member 27 is longitudinally slotted at 29 so that portions of frame head 26 may pass therethrough for engagement wit tubular member 25.

A hydraulic cylinder 30 extends within tubular member 18 and is pivoted at the'top thereof at3I. Cylinder 30 has piston 32 therein and piston 32 is pivoted at 33 to web 34 which is secured to-vacuum head 28.

Ears 35 and 36 are secured to tubular member 27 and extend outwardly on a diameter thereof (FIG. 2). A hydraulic cylinder 37 is pivoted at 38 to car 35 and a hydraulic cylinder 39 is pivoted at 40 to ear 36. Cylinder 37 has piston 41 therein also relate to boring or penetrating the earth.- The following U.S. Patsare considered to be pertinent:

Nos. 2,084,686; 2,301,478; 2,345,739; 2,723,835; 2,991,838 and 3,028,152. i

SUMMARY OF THE INVENTION The present invention is adisc cutter for. cutting discs from concrete or paved surfaces mounted on a' wheeled vehicle with the cutter mounted beneatha tripod supported frame. The frame and tripod with cutter and driving motors is raised and lowered into and out of position by a hydraulically actuated piston and cylinder with the cutter supported and moved .during' cutting action in-a' vertical direction by hydraulically actuated pistons and cylinders. The cutter is rotated by suitable hydraulic-actuated motors disposed about the periphery thereof. The cutter is a hollow cylinder having teeth disposed f about the lower periphery thereof mounted in ahead rotated by thernotors'and variousdiameter cutters may be used. A 1 vacuum actuated grab is disposed within the hollow cylindrical cutter and the vacuum is drawn therein when the cut is completed and when the separateddisc is to'beremoved from the-opening. The motor powering the wheeled support may also provide the hydraulic fluid under pressure for actuating hydraulic devices and this motor may also drive a vacuum pump for supplying'a'vacuum to the vacuum grab. H

W i I FIG. 4 is an enlarged detail of a portion of FIG. 3 showing a the construction of the vacuum grab; and

FIG. 5 shows schematically a suitable. hydraulic circuit for. use with theembodiment of FIG. 1.

oescarrrron or THE'PREFERRFDEMB'ODIMENT Referring now to FIGS. 1 and 2, a powered wheeled vehicle 10 supports on pivot ll and open frame 12' having side plates l3 and I4 and back plate 15. Suitable links 16 hold frame 12 in desired position and connect to the front of vehicle 10. A

pivot 17 is located across the. upper rearcornerof frame 12 between plates I3 and 14.

A hollow tubular member 18 which is square in cross section is mounted on pivot 17 and extends downwardly therefrom. Leg frarn'es 19, 20 and 21 are secured to member 27 and extend outwardly therefrom terminating in legs 22, 23'

and 24. respectively, which legs may be of adjustable length to provide a steady tripod support for the cutter when in work 75,

position.

and piston 41 is pivoted at 42 to ear 43 which is secured to cutter frame head 26. Cylinder 39 has piston 44 therein pivoted at 45 to ear 46 which is secured to cutter frame head 26. Frame-20 is'suitably apertured at 47, for cylinder 39.

' Referring now more particularly to FIG. 3, a circular bearing race 48 is secured beneath head 26 concentrically with tubular members 18, 25 and 27 as by bolts 49. A circular gear 50 is mounted for rotation on race 48. Cutter head 51 issuitably secured to gear 50 as by screws 52. A flexible resilient cylindrical apron 53 is secured to frame head 26 and laps and engages cutter head5l.

A suitable member of hydraulically actuated motors. 54, four in number as seen in FIG. 2, are mounted on frame head 26 and have drive shafts 55 extending therethrough. Each shaft 55 carries a gear 56 which meshes with ring gear 50.

Cutter head 51' is provided with a plurality 'of spaced con centric circular slots 57. The upperend of hollow cylindrical tool or cutter 58 is mounted 'in the slot 57 of the same diame- I ter allowing cutters of varying. diameters to beused. Cutter 58 has a plurality of openings 59 therein each receiving a lock lug 60; lugs 60 being secured to head 51 by lug screws 61 to hold cutter 58 in position in head 51. A plurality of spaced teeth 62 are mounted around the lower edge of cutter 58.

Vacuum head 28 has an upper-plate 63 (FIGS. 3 and 4) welded to tubular member 27 and a lower plate 64 secured thereto by bolts 65 and an annular tongue and groove 66. An annular seat member 67 is mounted beneath plate 64 and has an annular shoulder 68. A plurality of passages 69 extend through seat member 67 and open through shoulder 68. .A flexible resilient ring 70 is slidably mounted around plate 64 forming an annular chamber 71 with seat member 67. A pipe 72 opens through plate 64 and is connected to suitable vacuum producing apparatus, shown schematically in FIG. 3 and generally indicated at 73.

Apparatus 73 may include a vacuum pump 74 driven by the motor of vehicle 10 connected to a vacuum tank 75 and through a manually actuated valve 76 to pipe 72, suitable filters 77 being connectedin the system, as required.

A suitable hydraulic circuit for the embodiment of FIGS. 1- -4 is shown in FIG. 5. In FIG. 5 the hydraulic circuit includes a fluid reservoir having outlet pipe 79 passing through suction strainer 80 to the intake 81 of a double pump .82. Pump 82 is driven by the motor of a vehicle lllthrough shafi 83. Pump 82 The second side of pump 82 supplies fluid under pressure to pipe 89 to a two spool four-way stack valve 90 which may be two manually actuated four-way valves. Pipe 91 leads from valve 90 to cylinder 30 and return from cylinder 30 is through pipe 92 and valve 90 to reservoir 78 through pipe 93, return filter 94 and pipe 95.

Cylinders 37 and 39 are supplied with fluid under pressure from valve 90 through pipe'96 and are connected in parallel for uniform operation. Fluid is returned from cylinders 37 and 39 through pipe 97 and valve 98 to valve 90 and thence to reservoir 78 through pipe 93. Valve 98 is'a known type of pressure, temperature compensated flow control valve for accurate control of the rate of flow of fluid in one direction only compensating for pressure and temperature variations. Valve 98 when set for a particular flow rate will hold this flow rate regardless of pressure and temperature variations. Since valve 98 is in the return from cylinders 37 and 39 from their rod ends, the rate of movement of pistons 41 and 44 is accurately maintained together with the feed rate of cutter 58 preventing cutter teeth 62 from encountering excessive cutting forces when cutting materiai of varying hardness such as concrete with various typesoffaggregates and steel reinforcing rods.

The operation of the preferred embodiment of this invention is obvious from the preceding description thereof. The vehicle is moved to desired position and pump 82 energized. Valve 90 is then manually actuated to supply fluid under pressure to cylinder 30 lowering leg frames 19, and 21 and associated structure until legs 22, 23 and 24 engage the surface from which the disc is tp be removed. Vacuum pump 74 is energized and valve 76 actuated to connect vacuum to vacuum chamber 69, 71 and 71a through pipe 72 thereby drawing vacuum ring 70 into vacuum tight engagement with seat 67 and the surface of the disc to be severed. Valve 90 is then manually actuated to supply fluid under pressure to cylinders 37 and 39 thus lowering head 26 and cutter 58 until teeth 62 engage the surface. Valve 98 is then 'set for the desired feed rate for cutter 58 and valve 85 actuated to supply fluid under pressure to motors 54.

Energization of motors 54 rotates shafts 55 and gears 56 rotating ring gear 50, head 51 and cutter 58. Rotation of cutter 58 is continued until the cut is completed and a disc from the surface is then separated and located within cutter 58 and securely held by the vacuum mentioned above.

Valve 90 is then suitably actuated to supply fluid under pressure through pipe 92 to cylinder 30 to lift the entire structure from cutting position with vacuum head 28 lifting the severed disc from the cut. The disc may then be moved to any desired position and saved for reuse after the excavation has been filled.

Changes in or modifications to the above-described illustrative embodiment of the present invention may now be suggested to those skilled in the art without departing from the inventive concept herein. Reference should therefore be had to the appended claims to determine the scope of this invention.

l claim:

1. A disc cutter comprising a support, a first downwardly extending tubular member pivotally mounted in said support, a second tubular member slidably mounted on said first tubular member, a third tubular member slidably mounted on said second tubular member, leg frames secured to and extending outwardly from said third tubular member, legs extending downwardly from said frames, a cutter frame head extending outwardly from and secured to said second tubular member, first hydraulically actuated means extending between said cutter frame head and said third tubular member for raising and lowering said cutter frame head with respect to said first and said third tubular members, second hydraulically actuated means within said first tubular member and connected thereto and to said third tubular member for raising and lowering said second and said third tubular members with respect to said first tubular member, a hollow cylindrical cutter mounted for rotation beneath said cutter frame head, hydraulic motors on said cutter frame head for rotating said cutter, and means for supplying hydraulic fluid under pressure to said first and second hydraulically actuated means and to said motors.

2. A disc cutter as described in claim 1, said means for supplying hydraulic fluid under pressure to said first hydraulically actuated means including an adjustable pressure and temperature compensated flow control valve.

3. A disc cutter as described in claim 1 including a cutter head mounted for rotation beneath said cutter frame head a plurality of concentric circular grooves in said cutter head, t e

upper end of said cutter being received in one of said grooves and means for removably securing said cutter in said one of said grooves to said cutter head.

4. A disc cutter as described in claim 3 including a circular bearing race mounted beneath said cutter frame head, a ring gear carried by said race, said motors rotating said ring gear and said cutter head being secured to said ring gear.

5. A disc cutter as described in claim 1, said hollow cylindrical cutter including a plurality of teeth extending downwardly from and spaced about the lower end thereof.

6. A disc cutter as described in claim 1, including vacuum grab head attached to the lower end of said third tubular member, comprising a first circular plate secured to said third tubular member, a second circular plate secured beneath said first plate, an annular seat member secured beneath said second plate and extending peripherally outwardly therefrom, a flexible resilient ring slidably mounted around said second plate for seating on said annular seat member and means for supplying a vacuum to said grab head including a pipe passing through said plates and opening beneath said second plate and within said flexible resilient ring.

7. A disc cutter comprising a support, a first downwardly extending tubular member pivotally mounted in said support, a second tubular member slidably mounted on said first tubular member, a third tubular member slidably mounted on said second tubular member, leg frames secured to and extending outwardly from said third tubular member, legs extending downwardly from said frames, a cutter frame head extending outwardly from and secured to said-second tubular member, first means extending between said cutter frame head and said third tubular member for raising and lowering said cutter frame head with respect to said first and said third tubular members, second means within said first tubular member and connected thereto and to said third tubular member for raising and lowering said second and said third tubular members with respect to said first tubular member, a hollow cylindrical cutter mounted for rotation beneath said cutter frame head and concentric with said tubular members, motors on said cutter frame head for rotating said cutter, means for energizing said first and said second means, and means for energizing said motors.

8. A disc cutter as described in claim 7 including a cutter head mounted for rotation beneath said cutter frame head. A

plurality of concentric circular grooves in said cutter head, theupper end of said cutter being received in one of said grooves and means for removably securing said cutter in said one of said grooves to said cutter head.

9. A disc cutter as described in claim 8 including a circularbearing race mounted beneath said cutter frame head, a ring gear carried by said race, said motors rotating said ring gear and said cutter head being secured to said ring gear.

10. A disc cutter as described in claim 7, said hollow cylindrical cutter including a plurality of teeth extending downwardly from and spaced about the lower end thereof.

11. A disc cutter as described in claim 7 including a grab head attached to the lower end of said third tubular member, comprising a first circular plate secured to said third tubular member, a second circular plate secured beneath said first plate,'an annular seat member secured beneath said second plate and extending peripherally outwardly therefrom, a flexible resilient ring slidably mounted around said second plate for seating on said annular seat member and means for supplying a vacuum to said grab head including a pipe passing through said plates and opening beneath said second plate and within said flexible resilient ring. 

